Radiation before surgery more than doubles mesothelioma survival

Treating mesothelioma with radiation before surgery resulted in a 3-year survival rate that was more than double compared with that of treating with surgery first, according to new clinical research.

The findings, published in the Journal of Thoracic Oncology (doi:10.1097/JTO.0000000000000078), chart a viable route to treat patients more effectively and also improve their quality of life and potential survival, said principal investigator and lead author John Cho, MD, PhD, a radiation oncologist at Princess Margaret Cancer Centre, University Health Network (UHN) in Toronto, Canada.

“The patients in our study experienced shorter treatment, fewer complications, and speedier recovery,” said Cho. “The 3-year survival rate more than doubled to 72% from 32%.” Mesothelioma is an aggressive malignancy that starts in the lining of the lung and progressively restricts and invades the whole organ.

The study assessed a new approach dubbed SMART—Surgery for Mesothelioma After Radiation Therapy —and was completed over 4 years with 25 patients who had radiation therapy at Princess Margaret Cancer Centre and surgery at Toronto General Hospital, both part of UHN.

Participants were treated with an accelerated, 5-day course of intensity-modulated radiation therapy (IMRT), a specialized technique that conforms the radiation dose around the tumors in 3D while sparing the heart, spine, and other healthy tissues. The patients underwent surgery to remove the affected lung the following week.

“It was imperative to do the surgery quickly because the lung is particularly sensitive to radiation toxicity,” said thoracic surgeon and coauthor Marc de Perrot, MD, also of Princess Margaret Hospital. He noted that the SMART approach significantly reduced the treatment cycle for patients from 5 months to 1 month. It also reduced the risk of recurrence because the radiation wiped out the cancer’s ability to seed itself elsewhere in the chest or abdomen during surgery.

“These research results offer real hope to mesothelioma patients who have too often been told in the past that they may have only 6 months to live,” said de Perrot. Exposure to asbestos is the main cause of mesothelioma in the 500 new cases reported in Canada each year, a number that has essentially doubled in the past decade, he says.

“Individuals with known exposure to asbestos, who experience shortness of breath, weight loss, and fatigue for more than 3 weeks, need to see a doctor. A basic chest x-ray will show a pleural effusion (which appears as half the lung in white shadow), and that is the trigger to seek specialist care quickly. We need to shorten the diagnostic and treatment cycle in mesothelioma because we now have an approach that makes it possible to control the disease and improve quality of life for several years.”

Since the study, Cho and de Perrot have used the SMART approach to successfully treat 20 more patients.